A variety of tests for diagnosing disease, monitoring the course of disease and/or determining the effectiveness of treatment of a disease, involve obtaining plasma from a patient and performing tests on the plasma. Typically, blood is obtained from patient and processed to remove the cellular components to provide the plasma, wherein the processing includes (a) centrifuging the blood at high G forces for about 5-15 minutes so that the more dense cellular components can be concentrated at the bottom of the centrifuge tube, and the supernatant plasma can be removed, or (b) applying a few drops of blood to a lateral flow device wherein gravity and capillary forces provide for separating the plasma from the other components, and the separated plasma is wicked into an absorbent pad wherein test reagents react with the plasma.
However, processing blood by centrifugation generally involves transporting the blood sample to centralized laboratories containing centrifuges, which are operated by skilled laboratory personnel. This is costly, as it is time and labor intensive. Alternatively, lateral flow devices, which can be utilized outside of the laboratory, and without requiring skilled personnel, cannot easily produce the liquid plasma sample that is desired by most state of the art and accurate diagnostic tests.
The present invention provides for ameliorating at least some of the disadvantages of the prior art. These and other advantages of the present invention will be apparent from the description as set forth below.